Evaporation of volatile liquid compositions having utility in a gaseous state is well known for numerous purposes, including air fresheners, aromatherapy, and repelling insects. Dispensers for volatile compositions may be as simple as an open container or may include dispensing aids. Dispensing aids may be passive, such as an exposed wick to increase surface area for evaporation. They may be mechanical, such as an aerosol can dispenser or a fan. They may include heating a volatile liquid, with heat being generated by burning a candle, utilizing a butane flame, or utilizing a resistance heater powered by electricity, either a battery or household electric current. Heated dispensers suffer from one or more drawbacks of safety (flame), weight (battery or extension cord) or limited location of use (household electric current).
An aspect of this invention is a portable dispenser that generates heat to aid evaporation and dispersion of a volatile compound or compounds over an extended time, at least one hour, and preferably several hours, without flame or electric current.
Another aspect of this invention is a convection-driven vaporizing dispenser comprising a closed, insulated container having a bottom air inlet and a top air outlet, said container including therein confined solid or liquid reactants capable of producing a long-lasting, low-temperature exothermic chemical reaction when mixed with each other or exposed to air, and a volatile composition heatable by said reaction, and user-operable or user-compromisable means for preventing premature activation of the reaction ingredients.